Republican presidential candidate Sen. Marco Rubio (Fla.) and his son Anthony listen to Rep. Trey Gowdy's introduction during a campaign event in Spartanburg, S.C., on Wednesday. (Erik S. Lesser/European Pressphoto Agency)

OKATIE, S.C. — Sen. Marco Rubio (R-Fla.) took some of his most direct shots of the campaign at Donald Trump in South Carolina Thursday morning, adopting a more aggressive posture against the GOP presidential front-runner in this state than he has in others.

Rubio, who is coming off a bruising fifth-place finish in New Hampshire after a widely panned debate performance, accused Trump of lacking any substantive foreign policy experience and criticized his use of crude language at a recent campaign event.

Rubio also took on former Florida governor Jeb Bush and Sen. Ted Cruz (R-Tex.) on foreign policy and national security. He said no other candidate left in the race is as prepared in that area as he is.

“Donald Trump has zero foreign policy experience. Negotiating a hotel deal in another country is not foreign policy experience,” Rubio said of Trump.

During his remarks at a retirement community here, he took another dig at the mogul a few minutes later.

“Even in our political culture I teach my kids to be respectful. There are certain words you don’t say,” Rubio said, adding, “You turn on the TV and a leading presidential candidate is saying profanity from a stage.”

“Profanity from a stage,” Rubio repeated for effect.

At a New Hampshire campaign event this week, Trump repeated a crowd member’s insult of Cruz: “She said — I never expect to hear that from you again! — she said: 'He's a pussy.' That's terrible."

A Trump spokeswoman did not immediately respond to a request for comment.

Thursday’s remarks were notable since Rubio advisers have felt for much of the campaign that there is little upside to taking on Trump until the field narrows. Six candidates remain in the race.

They also reflected the political and social makeup of South Carolina, a mannerly state where defense and national security issues are central.

On a flight from New Hampshire to South Carolina on Wednesday, Rubio signaled that he was preparing to adopt a more hostile position toward his rivals.

Here in Okatie, Rubio referenced his widely mocked repetitions at the last debate and so did a supporter.

As far as “the robot stuff,” said one man, “let's keep in mind that the Terminator was elected twice in California.”